COLUMBIA, S.C. (AP) — Days after the official launch of his presidential bid, U.S. Sen. Cory Booker announced key staff hires in several early voting states on Monday, naming veteran political operatives to head up his campaign in some of the first critical battlegrounds of the 2020 voting calendar.

The hiring moves are the New Jersey Democrat's push for strength in some of the places where presidential hopefuls must mark successes if they're going to build crucial momentum leading into the primaries and caucuses.

Booker has named state directors in Iowa, New Hampshire and South Carolina. In Iowa, Mike Frosolone served as caucus director for the state House Democrats, successfully recruiting dozens of Democrats to seek office there. Erin Turmelle is leading the campaign in New Hampshire, where she oversaw the state party's 2018 midterm efforts. South Carolina's Christale Spain worked in political outreach for Vermont Sen. Bernie Sanders' 2016 bid and has served as executive director of the state Democratic Party.

In each state, the campaign also named senior advisors, posts that will likely fill a variety of roles and serve to formulate overall strategy in the states, where Booker and other hopefuls have already begun to spend considerable time. Joe O'Hern, a former Obama campaign field organizer and Iowa caucus veteran, will fill the post there. Former Obama campaign deputy director Sean Downey will fill the post in New Hampshire. In South Carolina, the role goes to Clay Middleton, a longtime aide to House Majority Whip Jim Clyburn and Hillary Clinton's 2016 state director.

Booker also named organizing and special projects directors in Iowa, as well as a communications team there, and a deputy state director in New Hampshire.

Booker plans to visit all three states in the next two weeks, starting with a trip to Iowa on Friday and Saturday. From there, he'll go to South Carolina - overlapping with at least one other presidential hopeful, U.S. Sen. Kirsten Gillibrand of New York, who's making her first trip to the state around that time. Booker plans to visit New Hampshire over Presidents' Day weekend.

Booker campaign manager Addisu Demissie said in a statement to The Associated Press the hires were aimed at "growing a grassroots movement to unite Americans and make change happen."

U.S. Sen. Cory Booker, D-NJ, speaks during a news conference outside of his home, Friday, Feb. 1, 2019, in Newark, N.J. Booker earlier in the day declared his bid for the presidency with a sweeping call to unite a deeply polarized nation around a "common purpose." (AP Photo/Julio Cortez)

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